Flat and curved display devices are widely applied to various electronic devices, such as mobile phones, personal wearable devices, televisions, in-vehicle devices, personal computers, digital cameras, handheld game consoles, and the like. However, with the improvement of specifications such as resolution and narrow bezel, the optical design in the display device also faces challenges.
Take liquid crystal display devices for example. Optical performance of a liquid crystal display is usually closely related to a backlight module disposed behind the display panel. A conventional backlight module can be roughly divided into two types: edge type backlight module and direct type backlight module. One type of the edge type backlight module reflects light from the lateral side of the display area using a concave reflecting element to introduce light into the display area, and then the light is reflected by a reflective sheet under beneath the display area, which generates backlight. However, this type of backlight module may produce a bright band on a side of the display area close to the light unit, thereby causing problems in use.